Arduino – Ethernet Shield 2

The Arduino Ethernet Shield 2 is a board that allows an Arduino board to connect to the internet. It is based on the Wiznet W5500 Ethernet chip and provides a network (IP) stack capable of both TCP and UDP. It supports up to eight simultaneous socket connections and is compatible with the Arduino Uno and Mega (using the Ethernet library). The Ethernet Shield 2 connects to an Arduino board using long wire-wrap headers extending through the Shield, which keeps the pin layout intact and allows another Shield to be stacked on top of it. It has a standard RJ-45 connection, with an integrated line transformer and Power over Ethernet enabled.

There is also an onboard micro-SD card slot, which can be used to store files for serving over the network. The shield also includes a reset controller, to ensure that the W5500 Ethernet module is properly reset on power-up. The current Shield supports a Power over Ethernet (PoE) module designed to extract power from a conventional twisted pair Category 5 Ethernet cable, but it does not come with a built-in PoE module, it is a separate component that must be added on. Arduino communicates with both the W5500 and SD card using the SPI bus (through the ICSP header). On the Uno, these pins are digital pins 10, 11, 12, and 13, and on the Mega, they are pins 50, 51, and 52. On both boards, pin 10 is used to select the W5500 and pin 4 for the SD card. These pins cannot be used for general I/O. The shield also has LEDs to indicate power, activity, and network link status.